Message transmission device



Jan. 6, 1942. E. H.- HEBERN MESSAGE TRANSMISSIONYDEVIGE Filed Nov. .8," 1958 1O Sheets-Sheet 1 why mwoow m m m m B'YEDMHRD HHEBERN' WT 95% I Jan. 6; 1942. E. H. HE'BERN 2,269,341

MESSAGE TRANSMISSION DEVICE Filed Nov: 8, 1938 10 Sheets-Sheet 2 I i I INVENTOR. EDWARD H. HEBERN M9", M7 ATTO NEY' E. H. HEBERN MESSAGE TRANSMISSION DEVICE Jan, 6, 1942 Filed NOV. 8, 1938 INJuMTIO/V 209 swag- Fi /2 BY 10 Sheets-Sheet 4 INVENTOR 0wAR0 HHEBERN A TTORNEY Jan. 6, 1942. Q a HEBERN 2,269,341

MESSAGE TRANSMISS ION DEVICE Filed Nov. 8, 1938 10 Sheets-Sheet 5 INVENTOR.

l E 0 v mnb H. HEB EEN BY aw-. n L m ATTORNEY Jan. 6, 1942. E. H. HEBERN 2,269,341

MESSAGE TRANSMIS SION DEVICE Filed NOV. 8, 1938 1Q Sheets-Sheet 7' INVENTOR.

EDWARD H HEBERN ATTOR EY.

Jan. 6, 1942. E. H. HEBERN 4 MESSAGE TRANSMISSION DEVICE Filed Nov. 8, 1958 10 Sheets-Sheet 10 INVENTOR.

EDWARD H. HEB ERN ATTO NEY' 7 unit of Figure 12. Y

Patented Jan. 6, 1942 NITED srAr 1 PM1EWI" ME-S'SAGRTRANSMISSION DEVICE Edward H. Hebern, Oakland. to'; International Code Machine 09mm, Keno, Nev a, corporation of N T Application November 8, 1938, (Cl. 178-22) 8 Claims.

control system which is particularly adaptable for the transmission of language messages and the printing of the same at the receiving station. 7

Another object is to provide for the transmission of a message at a rate considerably greater than that directly possible for a typist.

Yet another object is to provide a control system such that the transmission of control impulses and/or a message may be in code.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth or be apparent in the following description of a typical embodiment thereof, and in the accompanying drawings, in which,

Figure 1 is a plan view of a sending unit for use in the system.

Figure 2 is a side perspective of a rotary impulse control element of the unit.

Figure 3 is a fragmentary sectional elevation at 3-3 in Figure 1.

Figure 4 is a front elevation of the unit of Figure 1.

Figure 5 is a fragmentary rear elevation of the mechanism of the unit.

Figures 6 to 9 inclusive are sectional elevations at 6-6, 'il, 8-8 and 9-9 in Figure 1.

Figure 10 is a sectional elevation at Iii-l0 in Figure 5.

Figure 11 is an enlarged perspective andfragmentary view showing the mechanical control for the output switch of the sending unit and the circuit of the switch.

Figure 12 is a diagrammatic view of the mechunli tilgure 16 is a right-end view of the receiving Figure 17 is a reverse-face view of an element of Figure 16.

Figure 18- is a fragmentary perspective showing ,ofpart of the mechanism in axial section, and a switch control device of the unit.

Figure 19 is a fragmentary and somewhat diagrammatic view of the drive connections for the mechanism.

Figure 20 is a fragmentary rear perspective of the receiving unit.

Figure 21 is diagrammatic view showing an alternative receiving unit.

Figure22 is a diagrammatic perspective of a tape-controlled unit for sending the function impulses.

Figure 22a is an enlarged fragmentary face view of a tape for use in the sending unit or Figure 22. V zzFigure 23 is a plan view of the unit of Figure Figure 24 is a partly sectional elevation of the unit.

Figure 25 is a sectional elevation at 25-2t in Figure 23. 24Figure 26 is an elevation at 2$-26 in Figure Figure 27 is an end elevation of the unit of Figure 22.

Figure 28 is a fragmentary plan view of a ma- I chine for perforating a tape for its controlling use in the machine of Figures 22 to 27.

Figure 29 is an enlarged fragmentary section at 29-29 in Figure 28.

Figure 30 is a side elevation of the machine of Figure 28.

Figure 31 is an, enlarged fragmentary sectional view at Ii-ll in Figure 28.

Figure 32 is a generally diagrammatic showing of a system including the disclosed sending anism and electric circuits of a receiving unit for reconverting the transmitted impulses into functions.

Figure'13 is a plan view of the-receiving unit of Figure 12, a printing machine associated therewith being shown frasmentarily.

Figure 14 is a fragmentary elevation of printing machine." Figure 15 is a front elevationof the receiving I theand receiving units and arranged for various use combinations, with and without coding machines.

The disclosed, apparatus for carrying out the present invention essentially includes a sending unit 2| which is operable to produce difieren- -tiated electrical impulses for wire or radio transmission to a receiving unit l2! which is comtrolled'by the received impulses to cause the performance of anyone of a number of difierent functions which are represented by the original impulses, the device thus constituting a remote control. The present apparatus has been particularly designed for the remote control of a prlnt-= ing apparatus or typewriter P to reproduce and print out messages in accordance with an original message which is converted into a succession of significant impulses by the sending unit 2| which is operatedin the manner of a typewriter. The present sending un'it has a series of keys for selective operation to cause the emission of impulses which correspond to language characters or special operations of a printing mechanism to be controlled. Once a key of the sending unit 2| has been struck, the present apparatus automatically carries on to the performance of a desired function through the influence of the corresponding impulse 'on a receiving unit I.

By particular reference to Figures 1 to 11 inclusive, it will be seen that the present embodiment of the sending unit 2! is carried on a base 22 and includes'a constant-speed electric motor 23 for operating a speed-reducing drive gearing 24 thereof, together with fuses and suitable power connections for the motor. The mechanism for converting typewriter characters and operations into electric impulses is carried by a frame structure which comprises spaced and complementary end plates 25 and 26 fixed to the base 22 in opposed and mutually parallel relation and rigidly connected by a series of tie rods or bars 21, 28, 29 and 30 which are further utilized as will be brought out. A single-pole switch 3| is mounted on the outer side of the frame plate 25 and includes terminals 32 and 33 for connecting the switch in the output circuit for the unit.

Keybars 35 are pivotaliy and independently engaged with a common shaft 36 which is fixed in and between the frame plates 25 and 26 at a rearward point thereof adjacent the frame bottom, extend forwardly in generally horizontal position to a keyboard for the assembly, and carry usual keys 31 for selective engagement to depress the bars from their normal positions. As shown, twenty-eight keys 31 and corresponding keybars 35 are provided for producing impulses corresponding to the twenty-six letters of the English alphabet, a spacing of the letters between words, and a carriage return and line shift at the printer. three banks or rows at different levels in a usual manner for typewriters.

Each keybar 35 comprises a flat strip oi' metal having an ear portion 38 extending radially downwardly of its pivotal axis at the shaft 36 and having its extremity connected with the frame bar 21 by a tension spring 39 which is constantly operative to urge a raised positioning of the keybar. The lower frame bars 21 and 39 mount similar plates 4| which respectively extend upwardly and downwardly from said frame bars and are slotted from their free edges to slidably receive the keybars in their slots as a guiding and positioning means for the individual keybars, the latter being evenly spaced apart.

along the keyboard. Means are preferably provided to prevent the depression of more than one keybar at a time; as shown, a'laterally slotted angle plate 42 is mounted on the bar 21 for cooperation with the bar and the plate 4i thereon to provide an elongated space of uniform crosssection, said space being closed at its ends and containing a plurality of balls 43 of such diameter that only one keybar 35 may be depressed through their line at any time.

Members 44 are, independently pivoted intermediately thereof on a common pivot shaft 45 The keys 31 are arranged in which is mounted on and between the plates 25 and 25, said shaft being parallel to and in the same vertical planewith the shaft 39 on which the keybars'35 are pivoted. The members 44 are flat and are suitably retained in coplanar relation with the keybars as by the use of slotted plates 4| which are mounted on the upper frame bars 28 and 29 to respectively extend downwardly and upwardly from the bars and constantly receive the members 44 through their slots, it being noted that the plates lie at opposite sides of the pivotal axis defined at the shaft 45.

Lateral extensions 46 ofthe keybars 35 extend upwardly to normally engage the lower edges of the forward portions of the members 44 and hold the-portions of said members against the bar 28 as a stop means to limit the upward swinging of the keybars and members, the point of engagement of the extension and member preferably lying in a slot of the plate 4| on the frame bar 28, as is shown. A tension spring 41 connects each keybar 35 with the corresponding member 44 whereby the engagement of these elements is yieldlngly urged and normally maintained.

A shaft 49 is journalled in and between the frame plates 25 and 26 in parallel relation to the shaft 45 and slightly below the members 44, and carries forwardly extending and mutually parallel arms 49 and 50 fixed thereto adjacent the inner faces of the plate. A bar 52 is fixed to and between the forward ends of the arms 49 and 59 for its normal and simultaneous engagement with and beneath all of the members 44 when the same are in their normal and simultaneous engagement with and beneath all of the members 44 when the same are in their normal raised position. It will be noted that the assembly of the shaft 49, and arms 49 and 50, and bar 52 provides a rock-frame 53, and that a depression of a keybar 35 is, through the action of the corresponding spring 41, arranged to resiliently and yieldlngly urge a downward rocking of said rock-frame through the action of the corresponding member 44 on the bar 52.

An upward extension 49' of the arm 49 is arranged to effect the closing of the electric switch 3i when the frame 53 is sufficiently rocked in a manner hereinafter described. As shown, the extension 49' terminates in an ear 49" which extends transversely and freely over the top edge of the plate 25 and engages beneath a spring arm 54 comprising the movable contact element of the switch to normally dispose the contact point 55 of the element spaced from a fixed contact point 56 of the switch structure. A lever member 51 is intermediately pivoted on the plate 25 in generally horizontal disposition and with one end thereof engaged beneath the ear 49" while the other end is pulled downwardly by a tension spring 55 engaged between the latter end and an anchorage on the plate 25, the lever 51. being arranged to constantly and yieldlngly urge an upward swinging of the arm 49 to engage the bar 52 against all of the members 44.

It will now be noted that the possibility of lowering a member 44 sufficiently to effect a closing of the switch. 34 when a key 31 is depressed is controlled by the rotatively adjusted position of a unitary rotary element 60 Journalled in and between the frame plates 25 and 26. An axial spindle portion 5| of the element 60 carries weight discs 62 and 63 at its extending ends to increase the inertia of the assembly and counterbalance the element 60 which may in itself be unbalanced with respect to its axis. The spindle 6| also carries a gear 66 by which the element is arranged to be controllably rotated from the motor 23 through suitable connections with the motor gear 24, said connections including a clutch means for intermittent engagement while the motor operates the gear 2 at a fixed and predetermined rotative speed.

As shown in Figures 2 and 3, the portion of the spindle 6i between the plates 25 and 26 carries a series of like tubular spacers 64 alternating with relatively thin and flat rings 66 which have outer portions thereof extend as flanges beyond the cylinder of the spacers, there being a flange 66 for each key 31 and the circles of the flange peripheries being of like radius. The bores of the spacers 84 and flange rings 66 are axially grooved for receiving a spline key which extends along and from the spindle 6i whereby the rings may be held against rotation about the spindle. The assembly of the members t and G5 is arranged to be clamped between sleeves 69 releasably set on the spindle adjacent the plates and 26; as shown, the left-side extend from corresponding intermediate points I of the members 44, and the various flanges 66 are disposed in the planes of the rollers 61 for engagement by the different rollers, the axis of the element as being shown as disposed in a vertical plane through the common axial line of the raised rollers. Each of the flanges 66 is notched out longitudinally thereof whereby a cam action is provided with respect to a roller 61 which is free to follow the flange periphery. The flange notches 68 are ali of different lengths and preferably start at the same axial line of the flange cylinder whereby all of the rollers 61 may simultaneously overly an unnotched flange portion as a means to hold the switch 34 open.

Means are provided for rotating the element to through on revolution following the depression of any key 31, whereby, as the element rotates, the roller $1 of the member 44 which corresponds to that key may lower in the flange extension 46 from beneath the front end of the member 44 and so permit a sufficient pulling down of the member against the bar 52 of the rock frame 53 to rock said frame and permit a closing of the switch 34 as long as the roller is disposed in the flange notch. It will thus be understood that a rotation of the element while any key 31 is pressed down will result in a closin of the switch 34 for a definite period of time determined by the length of the notch 88 engaged by its corresponding roller 61, and that single electric impulses of different time length are produced as representing the different keys. It will be understood that the present structure of the element 60 is the operativ equivalent of a cylindrical drum having a Vshaped depression cut in its surface longitudinally thereof with one radial side of the depression extending axially of the drum and its other side extending spirally of the drum, or a cylindrical drum having arcuate grooves cut in its surface to receive the rollers 87.

In the present instance, the flange notches 68 are of progressively greater lengths from left to right along the element, the notch representing the letter Q being the shortest circumferentially of the roller and that representing the letter P being the longest. It will be understood, however, that the notches B8 of diflerent length might have any one of a large number of random arrangements along the element whereby a transmitted message may be correctly reconverted or translated by a receiver only if the relatic the lengths of impulses to language chara is known for use in making appropriate connections at the receiver. As is hereinhciore brought out, the roller 60 is adapted for a rearrang of the flanges, and the possible change of ch1 .C' ters to electrical impulses of different lengths is therefore in itself understood to comprise a cod-- ing device With respect to a transmitted message. Furthermore, the keys 3? may be actuated in accordance with a coded message whereby to increase the difliculty of decoding by an unauthorized person.

The present means for effecting a rotation of the element 60 to produce an electrical impulse of appropriate length each time a given key 3? is operated, includes a rock-frame it which is mounted beneath the keybars 35 and comprises arms H and 12 extending rigidly and forwardly from a shaft 13 journalled in the frame plates 25 audit, and connected at their forward ends by a bar 14 which closely underlies the keybars in such relation thereto that a full depression of any keybar against the bar ll is arranged to rock the frame '50 and lift the free extremity of a rear ward extension 12' of the arm l2.

A pivot pin 15 extends transversely from the free end of the extension 72' of the arm '32 through a slot in the plate 25 and mounts the lower end of an upright thrust bar it which is disposed opposite the outer face of the plate, the bar 16 being slidably held against the forward side of a stop pin IT on the plate by means of a tension spring 18 which is coactive between it and an anchorage on the plate. An arm 79 is pivoted on the outer face of the frame plate 26 near the top of the plate in generally horizontal disposition and with its pivot point at its forward end, and is normally held downwardly against the stop pin 11 by means of a tension spring #9 which is cooperative between it and an anchorage on the plate.

The plate 26 is transversely slotted from its top edge to provide a guideway for an arm at which extends from a pivotal connection with the frame bar 29 over and beyond the free end of the arm 18 to overlie'the top end of an upright arm 83 which is pivotally engaged with a support bracket 84 extending from a bottom point of the plate 26, said arms being arranged for a limited swinging in a common .plane. Tension springs 84 and 85 respectively urge movements of the arms 82 and 83 downwardly and toward the plate 26.

It will now be noted that a shaft 86 is mounted in and between the frame plates 25 and at for a slight longitudinal shifting thereof, and carries a gear 81 which is arranged to constantly mesh with the gear 85 on the trunnion 6! of the ele ment 60, and is of the same size as the latter gear. A gear 88 is mounted on the plate 25 for free rotation about'the shaft 85 coaxially thereof and in a fixed plane, is disposed between the gear 81 and the plate, and constantly meshes with the motor drive gear 28.

- The mutually opposed faces of the gears 87 and 88 mount complementary clutch plates 8? and 88' respectively for mutual engagement to complete a driving connection between the gears 24 and 85. Since the axial movement of the shaft 88 toward the motor will disengag the clutch plate 87' thereon from the other clutch plate 88', means are provided to constantly and yieldingly urgeran engagement of the clutch plates, and other means are provided to permit such engagement only while the element 88 is to be rotated. As is particularly shown in Figures 1 and 5, an helical spring 88 freely receives the shaft 88 and is compressedly seated between a collar member 88 adiustably fixed on the shaft and a sleeve 8| freely receiving the shaft and reactive with the plate 28 through an anti-friction bearing 82, whereby to urge an engaged condition of the clutch while permitting a rotation of the spring with the shaft.

At the end thereof which extends beyond the frame plate 28, the shaft 88 carries a disc 88, and a roller 88 mounted on the arm 83 constantly engages the outer face 83' of the disc 88 in a circular line adjacent its outer edge, a portion of the otherwise flat discfface-88' being dep'ressed in said line whereby the disc is'operative as a face cam with respect to the roller. 88 and the arm 88 which carries it. The under edge of the arm 82 is formed to provide an inwardly directed shoulder 85 which normally engages the outer end of the arm 83 to prevent an outward swinging of the latter arm from its normal upright position. When the arm 88 is secured by the shoulder 88 and the roller 98 engages the depression of the cam disc 83, the clutch plate 81' may engage the clutch plate 88', but when the shaft 88 is rotated to dispose th undepressed portion of the disc face against the roller the latter is reactive with the disc to shift the shaft 88 axially for disengaging the clutch to free the shaft and element 88 from the motor.

Since an actuated key 81 may be held depressed after its signal cycle is completed. means are preferably provided for automatically insuring a normal resecuring of the arm 88 by the shoulder 88 on the arm 82 independently of the key position and before a rotatlve cycle of the shaft 88 is completed. For this purpose, the lower edge of the arm 18 is cut away forwardly of its lower bearing face 88 which is engageable trailing end of the depression therein. With the motor energized and operating at a fixed speed, the depression of any key 81 frees the corresponding member 88 for its downward movement to permit a closing of the switch 88 in the described manner, and the rocking of the frame 78 simultaneously moves the thrust bar I8 upwardly to lift the arm 82 out of securing engagement with the arm 83 to free the latter to permit an engagement of the clutch and so set the shaft and element in rotation.

As the element 88 rotates, the roller 81 of the freed member 88 drops into the corresponding flange notch 88 toprovide a timed closing of the output circuit including the switch 8!. After the roller 81 has left the notch and again rides on the unnotched flange portion or is held clear of the flange by the returned keybar extension 8, the simultaneous rotation of the cam disc 88 is arranged to dispose the roller 88 in the depression'of the cam disc 88 to provide for the resecurwith the stop pin 1'! and the upper end of the thrust bar 18 from a point slightly forwardly of the pin 11. The arrangement is such that the bar 18 may engage the face 88 while in contact with the side of the pin 17, yet may not engage the arm 18 at all if it is swung forwardly from its pin-engaging position. For rendering the bar. 18 inoperative with respect to the arm 18, a cam projection 88 is provided on the shaft 88 for engaging the bar 18 to deflect it to an inoperative position with respect to the arm 18 before the roller 88 engages the depression of the cam disc 98 to release the clutch; in this manner, the arm 82 may descend to catch the top of the arm 88 behind the shoulder 88 while the roller engages I the depression. As shown, the cam projection is provided as a pin extending from the hub portion of the cam disc 88.

When the present sending apparatus is in condition for sending therewith, the member 88 is arranged to be so set rotatively thereof that the rollers of the members 88 engage the unnotched portions of the flanges 88 of the member adJacent the advance ends of the notches 88, the shoulder ing ofthe member 88 and the disengagement of the clutch as theroller leaves the depression. As the clutch is disengaged, a friction element or de-' tent 81 carried on a spring arm mounted on the base 22 engages a notch 88 in the periphery of the weight disc 88 for insuring a stopping of the rotary elements in their normal starting positions.

The control impulses produced by the sending unit 2! may be transmitted to a receiving unit l2l in any desired manner, as by wire or radio. The present device of producing electrical impulses of different timeduration to represent diflerent characters or functions lends itself particularly to radio transmission between sending and receiving stations, and such an arrangement is particularly indicated in Figures 11 and '12 wherein the output switch 8| is connected in series with a battery IOI and a suitable broadcasting unit I82 in which said impulses are amplified if necessary and are transformed into radio impulses of the same duration as the current impulses which give rise to them, all in a manner well known in the radio broadcasting art. The radio impulses from the broadcasting unit I82 are arranged for picking up to produce corresponding electric current impulses by a suitable radio receiver I03, said current impulses comprising the input to the receiving unit l2l for segregation thereby for operating the typewriter or printing device P for reproducing the original message or' performing a predetermined function.

It will be understood that the current output of the sending unit 2| may be sent to the receiving unit l2| directly by wire, with or without relay amplification, in lieu of by radio.

Essentially, the reconverslon into function operations of the impulses transmitted from the sending unit 2| to the receiving unit III is effected by selectively energizing at the receiving station the appropriate one of a plurality of local circuits connected in parallel and each controlling the operation of the printing unit P for printing the character or performing some other operation which corresponds to the received impulse, the operation being automatically controlled by the received signal impulse itself. Each of said local circuits is controlled in partby a.

multiple switch of the commutator type fwhereof its movable contact element is rotated at the same rotative rate as is theelement 88 of the unit 88 of the member 82 secures the arm 88,- and the roller 88 on the latter arm engages the undepressed portion of the cam face 88' adjacent the 2| which controls the duration of the Original" 7 control impulses, and-successively closes branch circuits thereat which correspond to characters or functions which are represented by impulses of progressively greater duration. A main switch controls all of the branch circuits and is automatically closed at the termination of an input impulse whereby to energize only the one branch circuit which corresponds to the duration of the impulse and is closed by the multiple switch.

The elements of the present receiving unit I2I are mounted on a common base I22 and include an electric motor I23 which is arranged to actuate a drive gear I24 of the motor assembly at a contant speed which may equal that for the sender motor 23. A major portion of the receiving mechanism is carried on a rigid frame structure which comprises spaced and-complementary side plates I25 and I25 fixed to the base I22 and connected by spacer bars I21, and a front plate I28 extending from the base I22 and fixed at its top to the upper front bar I21. The base I23 further mounts fuses and suitable power input connections for the motor and the local circuits of the units, including a pairof contacts I29 for connecting. the input circuit with the unit. I

A shaft ItI is journalled in and between th frame plates I25 and I26 and extends somewhat beyond each of the plates. A flywheel disc I32 is mounted on the shaft extension nearest the motor, and the shaft also carries a gear I83 fixed thereto adjacent the disc I32. The other end of the shaft I3I extends through and beyond a fixed contact plate providing a central contact ring I35 which is continuous, and a line of equally spaced contacts I36 at its outer face and arranged in the arc of a circle which is concentric with the shaft. An arm I31 extends radially from the shaft opposite the outer face of the plate ltd and carries brushes I38 and I39 connected by a conductor I40, said brushes being respectively operative at the ring I35 and the contacts I36 whereby the arm may provide a bridging connection between the contact ring and the clifierent contacts I35 as the arm is rotated. The contacts I35 are equally spaced in their line except for a gap which corresponds to a number of the contacts.

A counterweight I40 is mounted on the shaft portion between the plates I25 and I23 whereby the eccentric weight of the arm I31 may be counterbalanced. The plate I34 and arm I31 may be of a non-conducting material such as fibre or Bakelite, whereby to insulate the various contacts of each element from the shaft and from each other, and connections are provided for each of the contacts I35 and I35 at the back of the plate I35, as is brought out in Figure 16.

As shown, the brush arm I51 extends from the outer portion MI of a cylindric sleeve which recelves the shaft I3I and is clamped against the opposed end of an inner sleeve portion MI by a thumbscrew I 42 engaging axially in the shaft end, only the portion I4I' being directly fixed to the shaft. The opposed faces of the sleeve sections MI and NI are corrugated or roughened for their frictionally locked engagement by the screw I62 whereby a release of the screw permits an adjustment of the arm I31 rotatively of the shaft. As will hereinafter be brought out, the normal disposition of the bnish I39 of the arm I31 is at a certain point between the ends of the arcuate line of contacts I36 while the shaft ISI is releasably retained in a set position by a detent means which is operative against the disc I32, and rotary adjustment of the arm I31 on the shaft may therefore be necessary for pro viding a properly coordinated operation of mechanism, with reference to the sending unit which is to control its operation,

A shaft I43 is journalled in and between the frame ends I25 and I26 for both its rotation and a slight axial shifting thereof, and carries a gear I44 fixed thereto at its extremity nearest the motor for constant engagement with the gear on the shaft I3I, said gears being of like size whereby the shafts which respectively mount them may constantly have the same rotative positions and speeds. A gear I45 is mounted on the outer side of the plate I25 for free rotation. about the axis of the shaft I43 in a fixed plane, and constantly meshes with the motor drive gear I24. The mutually opposed faces of the gears I44 and I45 mount complementary clutch plates I44 and I45 respectively whereby to complete a driving connection between the gears I2 5 and I33 when the clutch plates are engaged.

Means are provided to constantly and yieldingly urge the shaft I43 axially thereof for main taining the engagement of the clutch plates, and other means are provided to permit such engage merit of the clutch plates only while the arm I81 and the shaft I43 are to be rotated. Asshown. an helical spring I45 freely receives the shaft I63 and is compressedly seated between. a collar member I41 adiustably mounted on the shaft and a sleeve I48 freely receiving the shaft and re a'ctive with the plate I25 through an anti-frie tion bearing I49 for permitting the rotation of the spring with the shaft. It will be noted that the clutch connections for the shaft its are sirni lar to those for the shaft of the sending unit 2I. I

A'lever member I5I having arms I52 and extending oppositely in generally parallel rela tion to the base I22 and an arm ltd extending downwardly from its pivot point is pivot-ally mounted on the outer face of frame plate I25 adjacent, its top. A tension IE6 is operative forwardly againstt he free end of arm I54 to urge a rotation of the member to a normal position in which the arm I53 A gages a stop pin I55 extending from the pie I26. An arm I55 is pivoted to the upper rear frame bar I21 for swinging on a plane transverse to the plate I25 said arm extending through and beyond a guide notch or slot provided in the top of the plate. The under of the arm I56 is normally held against the bot tom of the slot to dispose its outer portion close to but out of contact with the top of an up right swingable arm I51 which extends from pivot provided on a bracket mounted on the plate I25 near its bottom for swinging in the same plane with the arm I55, and closely overlies the arm I53 of the member I5I. As shown, downwardly directed lateral extension Itt' of the arm I55 is engaged by one end of a tension spring I55" which is operative between the free end of the arm I56 and an anchorage provided on the bar I21 which mounts the arm I55, where= by to yieldingly urge the engagement of the arm I55 against the slot bottom.

Intermediately thereof, the upright arm I51 carries a roller I59 which constantly and eccen== trically ngages the outer face I 66 of a disc cent IGI fixed on the extremity of the shaft I63. tension spring I51 is constantly operative he tween the arm I51 and an anchorage on the aforesaid bar I21 to urge a retention of the roller I59 against the cam face I68, but is not strong limit the outward swinging thereof. arm I51 is held by the shoulder I62, the roller enough to overcome the resistance of the spring I46 to effect the condition of the clutch device.

The annular portion of th cam face I66 which is engaged by the roller I59 is flat except for one relatively shortv arcuate depression therein for receiving the roller during part of each rotative cycle of the cam and its shaft I46.

It will now be noted that the under edge of the arm I56 is stepped to provide a rearwardly directcd shoulder I62 which normally engages the outer top corner of the arm I51 to positively When the the arm I5 following its release by raising the arm I56 to permit the engagement of the clutch and the rotation of the shaft.

The described mechanism for controlling the clutch is in a normal static condition when the brush, I59 engages the contact plat I34 at the beforementioned intermediatepoint of the contact plate, the arm I51 is held byv the shoulder I62, and, the roller I59 engages the undepressed portion of the cam face I66 adjacent the trailing end of the cam depression to hold the clutch disengaged, thisbeing the condition shown in the drawings. I

- Having the motor I 24 operating continuously at afixed predetermined speed, a pulling down of the forward arm I52 of the lever I5I is arranged to engage the rear arm I56 of the same member with the arm I 56 to lift the latter to free the arm I51 for its outward swinging under the influence of the shaft spring I46 and permit the engagement of the clutch I44I45; the latter results in a simultaneous and like rotation of the shafts I61 and I43. Just after the brush I39 has completed its traverse of the line of contacts I66, the roller I56 is arranged to engage the depression of the cam face I66 and so provide for reengagrng the arm M1 with the shoulder I62 as the continued rotation of the cam and shaft moves the roller out of the depression to release the clutch and permit a stopping of the mechanism in its original and normal condition.

it will now b noted that a roller I64 carried on a spring arm I65 extending from the base I22 constantly bears against the periphery of the disc I32 on the shaft I6I and is operative as a spring detent-in a notch I65 of the disc edge when the disc is in its normal static position. The shaft 266 of the roller I64 is arranged for its engagement by the top edge of the rear arm id! of a lever I66 which extends along the plate lit, is intermediately pivoted on said plate, and has its other arm I69 extend slightly forwardly of the front frame plate I28 and beneath the extremity of an arm I1I which is pivoted on the plate I26 in general parallelism to the base I22;

the arms I61 and I69 are shown as extending from a common hub and in relatively offset position transversely thereof. A tension spring IN is reactive with the arm IN to urge its engagement with a stop pin I12 which extends beneath it from the plate I28, the pin I12 being so located that the inner end of the lever I68 is held close disposal ofv the shoulder I62 for again securing to the roller shaft I66 when the pin is engaged by the arm "I.

A thrust bar I16 is carried by and extends upwardly from a pivotal connection with the arm I 1| and is urged to normally retain a. sliding enagement against a stop pin I14 which extends from the plate I26 through the action of a tension spring I16 which is reactive between it and the plate. The pin I14 is also normally engaged against the under side of an arm I15 of an horizontally disposed lever I16 having its other arm I11 engaged beneath a spring contact arm I18 of a switch I19, the arrangement being such that thecontact I8I of the switch arm I16 is held away from the fixed complementary switch contact I82 when the lever arm I15 engages the pin I14, the latter being constantly urged by the action of a spring I16 which is operative against the lever I16 with a strength sufficient to overcome the resilient resistance of the switch arm I18 to a separation of the contacts I H and I62 of the switch.

It will now be'noted that the'thrust bar I16 I is provided at its upper end with a shoulder or ill , its raised position during the displacement of said seat I16" which normally underlies the tip of the arm I15 of the lever I16 and is close to the latter when the arm engagesthe pin I12. Under these conditions, a raising of the bar I16 is arranged to engage its seat I16" with the lever arm I15 to rock the lever I16 and permit a closing of the switch I19. If, however, the'bar I16 should be swung away from the pin I12 before or while it is raised, it will be inoperative to engage the tip of the lever arm I15 and so may not then operate for raising the arm or holding it raised, the switch then being open as is normal. It will be understood that the displacement of the detent roller I64 while the disc I62 and other rotatable members are rotating during an operative cycle of the mechanism will act positively through the lever' I66 and the arm I" to lift the thrust bar I16 to roller.

An electromagnet I66 is provided for energizing and actuation to rock the bar I16 to an inoperativ relation to the switch control lever I16. As shown, the armature I66 of the electromagnet extends opposite and generally parallel to the bar I16 and has a pin I64 extending laterally therefrom into a longitudinal slot I65 provided in the upper bar and longitudinally of the bar. When a circuit which includes the solenoid I66" of the electromagnet I66 is closed, the resulting movement of the armature I66 against the resistance of the spring I16 enects the inoperative disposal of the bar I 16 as described. The arrangement is such that when the bar I16 Is swung sufficiently away from the pin I12 while in elevated position, the opposed extremity of the lever I16 may engage its side to prevent its return movement while it is held raised, as is the case as long as the roller I64 is out of the notch I65 of the disc I62.

An electromagnetic means is provided for actuating the lever I5I to release the clutch for starting a cycle of operations of the mechanism. As shown, an electromagnet I66 is mounted on the base I26 beneath the forward end of the lever arm I52 and with its normally spring-raised armature I66 movable in a vertical plane in or adjacent the plane of movement of the arm. A link I81 connects the free end of the armature I86 with the free end of the lever arm I52, and the depression of the armature I66 on account of an energizing of the electromagnet solenoid I88" is arranged to actuate the lever II to provide for the described cycle of operations of the apparatus.

An electromagnetic two-way switch I88 is provided having its coil or solenoid I88" connected in series between the input contacts I29 by means ,of wires 222. The armature I88 of the switch I88 is a conductor and its free end is alternatively engageabie with contacts I89 and I 90 when the switch solenoid is deenergized and energized respectively. It will, of course, be necessary that the current input for the solenoid I88" be strong enough to eifect a displacement of the armature from its normal engagement with the contact I89 to engage the contact I90 and against the resistance of a usual spring which normally holds the armature against the contact I89. As shown, the switch I98 is mounted on top of the frame of the described mechanism.

As is shown in Figures 12 and 13 and 22, the

typewriter or printing machine P for remote control through the present system is provided with a set of keys I9I corresponding to the keys 31 of the sending unit 2| and carried on keybars I99. Said keybars are arranged for individual actuation electromagnetically by the energizing of electromagnet coils I92 having movable cores I93 normally extended and provided with hooks I94 which engage over the keybars of the various keys for rocking the keybars when their corresponding electromagnets are energized. The set of eiectromagnet assemblies may be provided as a part of the printing unit P, or as a separate key-operating unit K for the engagement of its solenoid-controlled hooks I94 with the keybars of the printer? in either event, the combination P-K is understood to comprise an electrically actuated printer or typewriter. It is to be understood that the unit P generally, represents mechanisms adaptable to remote control such, for instance, as air and water craft, explosive mines, etc.

The circuits of the unit I2I derive their operatgaged by a spring contact arm ii I of a switch 2I2 whereby to engage a contact of said arm with a complementary contact of a second spring arm 2I3 of the switch. The switch 2I2 is arranged for inclusion in a controlled circuit which is closed at the switch while the bar I13 is held away from the pin I12 by the energized electromagnet I83 and/or the lever I16. It will be noted that the switch 2I2 is held closed mechanically after the circuit of the switch I13 is reopened in each cycle of operations of the receiving unit whereby the function of its circuit is generally supplementary to the functions of the multiple circuits controlled by the commutator switch assembly I34, and endures until the cycle is terminated and the bar I13 is lowered to move away from the solenoid and so reopen the switch.

' The arrangement is understood to constitute a relay switch with respect to the circuit of the switch 2I2.

Having the various working parts of the present receiving unit I2I in the normal conditions described and shown for them, the motor I23 operating at the required speed, and the two mutually parallel circuits controlled by the switch I98 both open, an output current impulse from the radio receiver I83 is operative, to enter gize the solenoid I89" to cause the engagement of the armature I98 with the contact I99 and so close the circuit of the electromagnet its to rock the lever ISI and initiate a cycle of operations of the mechanism by causing the engage ment of the drive clutch. When the actuating impulse ceases, the armature I83 again engages the contact I89 to close thereat the circuit which includes the contact ring I35, the connected brushes on the contact arm I31, a contact I133 which is then engaged by the brush I39, a solenoid I92 connected with the engaged contact I36, the switch I19, and the solenoid of the electromagnet I83.

Referring particularly to the primary output circuit which includes the normally open switch ing current from power input wires or conductors I98 and, I99 which may also supply the power for the motor I24, as is indicated. As shown, a conductor wire 2M connects the armature switch arm I83 of the switch I88 with the power wire I99, a wire 292 connects the contact I90 of the switch I88 withone terminal of the solenoid I96", and a wire 293 connects the other terminal of the solenoid I88" with the power wire I99, said connections providing a normally open circuit which requires only the closing of the switch I88 at the contact I98 to energize the solenoid I98".

A wire 285 extends from the contact I89 .0! the two-way switch I38 to the contact ring I38 01 the contact plate I34, wires 289 connect thediiierentcontacts I38 with one terminal of each of the diflerent key-operating solenoids I92, and a common return wire 291 connects the other soienoid terminals with the arm contact I8I of the switch I19; the arrangement is understood to provide mutually parallel branch circuits between the ring I and the switch I19. The switch contact I82 is connected with a terminal of the solenoid I83" of the electromagnet I83 by a wire 208, and a'wire 289 connects the other solenoid terminal with the power wire I 99 to complete a selective control circuit for the functions to be performed, said circuit comprising in part an output circuit for the receiving unit I2I.

By reference to Figures 13 and 15 and 18 and 21, it will be seen that the armature I83 is en- I13, it will be noted that the displacement of the detent roller I64 to ride on the edge of the disc I32 during a rotation of the disc Is arranged to lift the bar I13 to rock the lever I13 to permit a closing of the circuit at the switch I13. Assuming that the brush I39 is engaging a contact I863 when the input current ceases, the reengagemene of the armature I89 of the switch I88 with the contact I89 provides a, completely closed circuit through the electromagnet I92 whereby to actuate a keybar or other element of the printing mechanism which corresponds to the contact in the circuit. This establishing of a current through the solenoid I33" of the eiectromagnet I83 results 'in an actuation of the armature I33 to pull the bar I13 from beneath the arm I13 of the lever I16 and so permit a, swinging of the lever to engage the stop I12 and open the switch I19 by the action of the spring I19. It will he understood that there is a time lag between the energizing of the circuit and the opening oi the switch I19 which is normally sumcient to permit I92 before the switch is switch I88. Accordingly, the relay switch 2I8 will be held closed only for the balance of an operative cycle which was started by the impulse, whereby the time duration of the closing of said switch will vary inversely with the duration of the actuating impulse. As shown, a wire 2I8 leads from the power, wire I88 to one terminal of a lamp 2I8, 9, wire 2L1 leads from the other lamp terminal to the arm 2I8 of the switch 2I2, and a wire 2I8 leads from the switch arm 2 to the other power wire I 99 to provide a supplementary circuit for the lamp 2I8 which is lit as a telltale only after an electromagnet I92 has been energized and deenergized in a cycle; the supplementary circuit of the switch 2I2 may obviously control some other device, or devices than a lamp, however.

It will be understood that the rotative speed of the contact arm I81 of the receiving unit I2I must be so synchronized with the rotative speed of the impulse-timing element 88 of the sending,

unit 2| that the proper output circuit may be energized as the impulse ceases. For providing this relation, the rotative rates of the element 80 and arm I31 are, in the present instance, de-

signed to be equal, this being accomplished by having the respective drive motors 28 and I28 comprise like alternating current synchronous motors which automatically operate at fixed speeds'in terms of the frequency of alternations of the operating current. With the gearing connections the same for both motors, ity is merely necessary to supply operating power thereto from alternating current sources of like frequency whereby the required synchronized operation of th sending and receiving units may be provided.

7 Also, the first contact I26 which is engaged by the brush I88 on the contact arm I81 during a rotative cycle thereof must be reached by the brush from its starting position at rest in the time of the shortest signal impulse, and it will be recalled that the described provision for rotating the arm I81 on the shaft I3I permits this vital setting of the arm for its timed operation.

While the operation of the solenoids I82 may be sufliciently rapid to complete their work in the short time permitted by the operation of the unit I2I, it has sometimes been found desirable to utilize the output current corresponding to a. particular impulse to operate a relay switch which may maintain its secondary circuit for the time that the switch 2I2 is closed, and so insure the performance of a function which requires more power and/or time than is provided by the rotary contact device of the unit I2I. Accordin'gly, and as shown in Figure 21, a. receiving unit 2|! is provided for energizing electromagnetic relays 228 in lieu of the solenoids I82 of the unit K for operating a printing, machine or other mechanism to be controlled. The solenoids 22I of the said relays are connected with different contacts I88 by means of the wires 288 and with the switch I 18 by the common conductor 281, and are arranged for the continued closing of the switches 222 or their secondary circuits until an impulse cycle is completed for the relay switch 228 thus provided, this arrangement essentially comprising a delayed action for the opening of the switch 2I2.

As is particularly shown, the relays 228 are of similar structure to th relay I88-2I2 of the unit 22!, and their armatures are arranged for control with and in the same manner as the armature I82 of the first relay. The'control lever 228 which carries a roller I at its inner end to engage the notch ass of the disc m in the described manner replaces the lever I88 and is part of a rock-frame 228 which fixedly carries a contact bar 225 at its forward end to engage beneath corresponding ends of a bank of similar levers 228 which correspond to the lever I'll and are rotatively pivoted on a fixedly mounted shaft 221. The bar 225 and shaft 221 are mutually parallel to each other and to the pivotal axis of the rock frame 225. One of the levers 228 carries a thrust bar I13 for control at the relay I882I2 as before, and the remaining levers 228 carry corresponding and similar thrust bars 228 for control as the bar I18, and with respect to the difierent relays 228.

A stop bar 228 extends opposite the members I13 and 228 adajacent their upper ends and at the opposite side thereof from the various relay armatures to which they are connected by pins I84 engaged in longitudinal slots at the bar ends, and springs 28I are normally operative to yieldingly hold the members against the bar 228. The latter bar is operative as the pin I12 of the unit HI, and when the members I18 and 228 are in lowered position, seats I88 of the members lie just below the top line of the bar. A lever I18 is operative at the bar I18 to control a fixedly mounted switch assembly I18 and the disposal of the bar with respect to the solenoid I88 in the previously described manner, and levers 282 are provided which correspond to the arms I18 of the lever I18 and are coactive with the various trust bars 228 in the same manner. Springs 288 are constantly operative to urge the levers 232 to engage the top of the stop bar 228. It

will be understood that when an electromagnet 22I is energized, with the corresponding bar 228 raised, the latter bar is displaced to close its switch 222 and permit the engagement of the opposed end of the lever 282 against its outer edge to maintain a closed condition of the switch until the bar is lowered by the engagement of the roller I84 in the notch I68 of the disc I82. It will be understood that although all of the thrust bars 228 are held raised during an operative cycle of the commutator switch of the unit, only the switch H2 and one switch 222 will be closed during the cycle.

With the present unit 2 II in its normal receiving condition, an output current impulse reaching the solenoid I88" through the wires 288 is operative to energize the solenoid to cause the closing of the switch at the con-tact I88 and so close the circuit of the electromagnet I88 to rock the lever I5I through the link I81 and so initiate a cycle of operations of the mechanism by causing an engagement of the drive clutch and the rotation of the arm I31. when the actuating impulse ceases, the armature I88 again engages the contact I89 to close thereat a circuit which includes the contact ring I88, the connected brushes on the arm I81, a contact I88 which is then engaged by the brush I88, the solenoid of a relay 228 corresponding to the engaged contact I38, the switch I18, and the solenoid of the electromagnet I83.

Since the engagement of the clutch has caused the rotation of the disc I82 to rock the lever 228 and so raise all of the thrust bars I18 and 228 to displace the arms I18 and 282 respectively, the energ zing of the last aforesaid circuit will erfect a displacement of the bar I18 and the bar 228 of the then energized relay switch to open the said circuit and close the working or function circuits of the switch U2 and the appropriate switch 222. In this manner, the automatically selected function circuit 230 of a switch 222 will be held closed at its switch until the original quiescent status of the unit H9 is restored. The operations of the function circuits may be the control of a printing machine P, as with the electromagnets I92, the selective remote control of mechanical equipment or vehicles, the firing of guns or mines, and the actuation of other devices. It will be understood that a succession of function impulses in a particular and predetermined order may be required and utilized to cause the performance of a, particular function; this may be termed a coded control.

Recalling that but a single impulse is required for production and transmission and translation by the present; device to energize a given function circuit, it will be noted that the sending of impulses representing language characters is limited only by the speed of a typist rather than the slower speed per character of a telegraph or teletype operator. it being recalled that a plurality of mutually timed operations to represent a character must be effected in the latter instances. Also, the present device in no way in volves the relative timing of successive impulses as required with the other mentioned devices, since each impulse of a succession of impulses is independent of every other for function-controlling purposes, its timing being related only to its own cycle of origin. It will therefore be understood that the sending of messages with the present apparatus may be several times as fast as by telegraph or teletype," and has the further advantage of directly printing the transmitted characters and message.

Under some circumstances, as in wartime communication between spaced points, it may be desirable to transmit a message at a still greater speed than a typist may send it directly. As is shown in Figures 28 to 31, a unit 30! is provided to convert a typed message into perforations in a tape which may thereafter be run through the sending unit 24! shown in Figures 22 to 27 and arranged for actuation to provide the output impulses at a mechanically controlled speed which is very much higher than possible human speed; the present apparatus may effect the transmission and reconversion of the character impulses at the rate of sixhundred or more per minute.

Aside from the coding which'is directly possible through varying the significance of the impulses sent to the receiving units |2| or M9, the keys of the sending unit 2! or of the tape-marking unit 30| may be operated in terms of a lengths,

. mounted on a base plate 245 which carries an coded message, or the latter units may be directly operated automatically from a cipher machine such as is described in my copending application Serial Number 232,995, filed October 3, 1938. When a cipher machine is used for sending .a language message, the output circuit of the receiving unit 13! or 2? would have a corresponding deciphering machine operatively interposed between it and the printing machine P.

As is illustrated, the sending unit 24! is arranged for operation in accordance with a longitudinal line of perforations on a control tape 242 for effecting the emission of function impulses of variable length and corresponding to the impulses which may be sent. out from the sending unit 3| which it may replace in a remote control system utilizing th'e receiving units i2i or H9. The successive tape perforations 243 are each variably spaced from each other along the tape to represent impulses of difierent electric motor 246 arranged to drive a gear 241 of its assembly at a predetermined speed, and suitable power connections including wires 246 and 249. A shaft 252 carries a gear 253 at one end thereof and in constant engagement with the motor gear 241, and is journalled in a bearing sleeve 254 which is fixed on a bracket plate 255 extending from the base 245. The shaft 252 is parallel to the shaft of the gear 249, and an anti-friction thrust bearing 256 is operatively engaged between the gear 253 and the opposed end of the sleeve 254.

The plate 255 mounts a single-pole switch 251 having a fixed contact 256, and a movable contact 259 of the switch is carried on a. spring arm 26! which is normally spaced from the contact 256 to maintain an open condition of the switch. An arm 262 is fixed on and extends radially from the other end of the shaft 252, and said arm is operative for engaging the spring switch arm 26! once in eachrevolution of the shaft 252 to engage the contacts 259 with the contact 258 to close the switch 251. As particularly shown, the arm 262 carries a. cam projection 263 which is operative against an extension of the contact 259 which lies in the circular path of movement of the cam projection 263, the latter being suitably insulated from the arm, or itself being of electrically non-conducting material.

Mutually spaced brackets 263 and 264 and 265 extend upwardly from the base plate 245 and provide bearings which rotatively carry a shaft 266 in alignment with the shaft 252 and for its axial. shifting. The mutually opposed extremities of the shafts 252 and 266 between the brackets 255 and 263 carry clutch plates 261 and 266 respectively for mutual engagement for the driving of the shaft 266 from the shaft 252. An helical spring 269 encircles the shaft 266 between the brackets 263 and 264 and is constantly operative between the bracket 263 and a collar 2" fixed on the shaft to yieldingly effect a released disposal of the clutch plate 269. The collar 2" may engage the bracket 264 to limit the clutch-disengaging movement of the shaft 266.

The end of the shaft 266 beyond the bracket 265 is provided with a bearing socket 212 for receiving the extremity of a pin 213 carried by an arm 214 in a. plane including the shaft axis and extends transversely of the shaft opposite said end thereof. As illustrated, the arm 214 is pivoted at an end thereof to the base 245 for movement in a plane parallel to said base, and provides the shaft-engaging pin 2,13 intermediately of its the shaft 266 is disposed length.

A lateral extension 264 of the bracket 264 carries an electromagnet 215 opposite the free end of the arm 2" with its axis in the plane of movement of the arm and transverse to the arm, and with the outer end of the armature 215' of the electromagnet pivotally engaged with the arm end. The armature 215' is arranged to be extended from the electromagnet coil 215".while to disengage the clutch 261-266, and an energizing of the electromagnet is arranged to swing the arm 214 to axially snift which is pivoted for its swinging the shaft 266 against the resistance of the spring 268 and so engage the clutch for effecting a rotation of the shaft 266 with and from the shaft 252.

When the arm 214 is displaced by the action of the eiectromagnet 218 to engage the clutch, it is arranged to simultaneously close an otherwise open switch 216 which controls the output circuit for the unit. As shown, said arm carries a. contact 211 for engaging a fixed contact 218 mounted on the base 245, each of said contacts being electrically insulated from the elements which support them. In the present instance, and as indicated in Figure 22, the switch 216 controls the input to a suitable radio transmitting unit as does the switch 8! of the sending unit 2!.

It will now be noted that the rotation of the shaft 266 is arranged to effect a longitudinal feeding movement of the perforated tap'e 242 in a suitable guideway which includes a support member 218 providing a trough-like guideway portion in which the tape may be longitudinally moved and guided. The member 218 supports a, switch 28! which comprises a pair of mutually parallel spring arms 282 and 288 having contacts 282' and 288' for engagement to close a circuit including the switch. The free ends of the arms 282 and 288 extend over the center of the guideway of the member 218 in gen-- erally parallel relation thereto and to each other, and the lower arm 288 has a conical pin or finger '284 depending transversely therefrom to ride on trol finger 284, the tape is passed between feed rollers 285 and 288 which are located in advance thereof the roller 285 is provided with toothed friction flanges 288 for gripping the tape sides against the roller 286, and the tape-engaging face of the roller 286 is a true cylinder. A spring 288 isnormally operative against the frame 281 to resiliently and yieldingly urge the roller 288 toward the roller ass, while gears m and zszelectrically parallel and the switch 28!. As shown. a wire 288 connects the power wire 248 with one terminal of the coil 2'15", wires 284 and 285 connect the other coil terminal with terminals of the switches 281 and 28! respectively, and a wire 288 connects the other switch terminals with the power wire 248.

With the motor 248 operating the shaft 282 at a constant and predetermined rotative speed, the clutch 281-268 disengaged, and the finger 284 of the switch 28! engaged in a tape hole 248 whereby the switch is then open, the continued rotation of the shaft 252 will effect a closing of the switch251 through the-action of the arm 262 thereon and so energize the coil 251 to cause an engagement of the clutch and an advance movement of the tape 242' laterally from beneath the finger 284 and so lift the latter to close the switch 28!. The closing of the switch 251 is arranged to endure long'enough to insure the closing of the switch 28! before the switch 281 may open, and thus maintainthe energizing of the electromagnet until the finger 284 engages the succeeding tape ,hole 248. In this manner, the circuit of the switch 216 is arranged to be held closed for a time period which endures from the closing of the switch 251 through the closing and reopening of the switch 28!, and it will thus be understood that the relative spacing of successive holes 2'48 of the tape alone determines the length of impulse provided by the circuit of the switch 218.

A suitable means is provided for perforating a tape for use in the unit 24! to create endurancedifferentiated impulses inthe described manner.

As is shown in Figures 28 to 31 inclusive, a tapeperforating unit 88! is provided for the purpose, said unit being arranged for manual operation in the manner of a typewriter. The mechanism of the unit 88! is mounted on the pair of side plates 882 and 888 which extendupwardly from a base plate 884 to which they are fixed in mutually parallel relation. At an end thereof which extends forwardly beyond the base plate 884, and at its outer face, the plate 882 mounts a spool 888 which is arranged to carry a roll of the unperforated tape 242 for its advancement and perforating in the unit by reason of theselective actuation of the keys 888 of the unit.

The keys 888 are provided at the free forward ends of keybars 881 which at their rearward ends pivotally engage a common pivot shaft 888 fixed in and between the plates 882 and 888. The arrangement of the keys 888 may be any suitable one at the keyboard portion of the unit; as shown. the keys are arranged in three lines which are mutually stepped down toward the unit front. and the keys are equally spaced in their lines, all in a usual arrangement for typewriter keyboards. Fixed cross-bars 888 and 8!! at the front of the frame are operative to provide stops to limit the possible angular oscillation of the various keybars between raised and depressed positions thereof. As shown, the bar 888 overlies the keybars at a line adjacent the rear line of the keys, and individual tension springs 8!! are constantly operative between the keybars and. an upper crossbar 8 of the frame to yieldingly urge and normally maintain a raised positioning of the keybars against the stop bar 888. As shown, the springs 8l2 are secured to the bar 8 by means of eye-bolts 8 whereby the spring tension may be adjusted as desired.

A shaft 8! 6 is Journailed in and between the plates 482 and 488 and extends beyond the plate 882. The shaft 8 I 6 carries a set of ratchet wheel: 

